DRIVE UNIT AND DRIVE ARRANGEMENT

Description

[0001] The invention relates to a drive unit for a drive train of an electrically driven motor vehicle, in particular a hybrid motor vehicle, and to a drive arrangement.

[0002] Various drive units are known from the state of the art that are integrated into drive arrangements or drive trains.

[0003] DE 11 2015 006 071 T5 discloses a hybrid vehicle drive system comprising a generator capable of generating electrical energy using the power of an internal combustion engine; an electric motor driven by electrical energy to drive wheels; a housing housing the generator and the electric motor; and a power control unit for controlling the generator and the electric motor. The generator and the electric motor are arranged side by side on the same axis in the housing.

[0004] WO 2019 101 264 A1 discloses a drivetrain for a hybrid motor vehicle. The drivetrain comprises a transmission input shaft, which is operatively connected to a first electric motor and an internal combustion engine via a first drivetrain sub-unit for transmitting torque, and which is operatively connected to a second electric motor for transmitting torque via a second drivetrain sub-unit. The two electric motors are arranged coaxially and axially adjacent to one another.

[0005] EP 1 464 876 A2 discloses a drive train in which the two electric motors are nested radially and axially. Furthermore, WO 2011 / 054097 A1 discloses a drive unit that can be read off from the preamble of claim 1.

[0006] US 2016 / 0218584 A1 describes a control unit used to control electrical machines. The control unit is mounted on a housing of the drive unit comprising the electrical machines. The drive unit comprises two electrical machines arranged coaxially and axially adjacent to each other.

[0007] Integrating a drive unit with multiple electric rotary motors into a drive arrangement intended for a hybrid vehicle is subject to strict space requirements, particularly in the axial direction. A particularly short axial drive arrangement is advantageous, particularly when using such a drive unit in so-called front-transverse arrangements in motor vehicles, in which the electric rotary motors and the internal combustion engine are used as front-wheel drives and a respective rotational axis of an electric rotary motor and the internal combustion engine is arranged transversely to the longitudinal direction of the vehicle.

[0008] Based on this, the present invention is based on the object of providing a drive unit and a drive arrangement equipped therewith, which ensure optimal operation in a cost-effective design and in a space-saving manner.

[0009] The object is achieved by the drive unit according to the invention as defined in claim 1. Advantageous embodiments of the drive unit are defined in subclaims 2 to 7.

[0010] In addition, a drive arrangement comprising the drive unit is provided according to claim 8. An advantageous embodiment of the drive arrangement is specified in subclaim 9.

[0011] The features of the claims can be combined in any technically reasonable manner, whereby the explanations from the following description as well as features from the figures can also be used to comprise additional embodiments of the invention.

[0012] In the context of the present invention, the terms "axial" and "radial" always refer to the rotational axis of the drive unit, which corresponds to the rotational axis of at least one of the electrical rotary machines comprised by the drive unit.

[0013] The invention relates to a drive unit for a drive train of an electrically driven motor vehicle, in particular a hybrid motor vehicle. The drive unit comprises a first electric rotary machine and a second electric rotary machine and a first shaft and a second shaft, wherein a rotor of the first electric rotary machine is connected in a rotationally fixed manner to the first shaft and a rotor of the second electric rotary machine is connected in a rotationally fixed manner to the second shaft. The drive unit furthermore has a separating clutch with which the rotor of the first electric rotary machine is or can be connected to the second shaft for torque transmission. According to the invention, one of the two electric rotary machines is arranged at least partially radially and axially within a space radially delimited by the respective other electric rotary machine.

[0014] In one embodiment, it can be provided that the radially inner electrical rotary machine is arranged radially and axially completely within a space radially delimited by the other electrical rotary machine.

[0015] The separating clutch is arranged in a torque transmission path extending from the first electric rotary machine to the second shaft, or is configured to open and close this torque transmission path. The drive unit can comprise an actuation system for actuating the separating clutch, wherein a release bearing of the actuation system can be designed as a single-row or double-row assembly. According to the invention, the rotational axes of the rotors of the electric rotary machines are positioned coaxially.

[0016] The radial nesting of the two electric rotary machines has the advantage that when manufacturing the individual laminations of the rotor package and the stator package of both electric rotary machines from a blank with one punching stroke, both a lamination of the rotor of the radially inner electric rotary machine and the stator of the radially inner electric rotary machine and also the stator of the radially outer electric rotary machine and the rotor of the radially outer electric rotary machine can be cut out.

[0017] For the purpose of its connection to the second shaft, the rotor of the radially outer electric rotary machine can be carried by a rotor carrier which is connected to the second shaft, wherein the rotor is in particular connected to the rotor carrier in a force-fitting and / or form-fitting manner and the rotor carrier is connected to the second shaft in a force-fitting and / or form-fitting manner.

[0018] For the rotatable mounting of the first shaft and / or the second shaft, the drive unit can have a central bearing or a central bearing unit, which is designed in one or more parts and by means of which the first shaft and / or the second shaft are mounted on a housing of the drive unit. The rotor carrier of the radially outer electric rotary machine can be mounted directly on the central bearing or indirectly on the central bearing via the second shaft. The central bearing is designed, for example, as a roller, ball, or angular contact ball bearing.

[0019] The drive unit may comprise a fastening element which is bolted to the first or second shaft for securing the position of the rotor carrier of the radially outer electric rotary machine with respect to the position of the second shaft.

[0020] Advantageously, the radially inner electric rotary machine can be operated as a generator. The rotor of the radially inner electric rotary machine is relatively small and thus has a lower moment of inertia than the rotor of the radially outer rotary machine.

[0021] Accordingly, the radially outer electric rotary machine can advantageously be used as a drive unit, since the rotor of this electric rotary machine is relatively large and can generate a correspondingly large torque.

[0022] This does not preclude the possibility of using both the radially inner electric rotary machine and the radially outer electric rotary machine to drive a motor vehicle equipped with the drive unit. For example, the radially inner electric rotary machine can be used to transmit torque to an input side of the drive unit, enabling the start of an internal combustion engine connected to the input side. Alternatively, one or both electric rotary machines can provide torque and, together with a connected internal combustion engine, realize hybrid operation of the drive unit.

[0023] In one embodiment, the first electric rotary machine is arranged at least partially radially and axially within a space radially delimited by the second electric rotary machine.

[0024] The first electric rotary machine is designed as an internal rotor motor, and the second electric rotary machine is designed as an external rotor motor, with the stator of the first electric rotary machine and the stator of the second electric rotary machine being mechanically fixed to one another. Accordingly, one embodiment provides for the rotor of the first electric rotary machine to be arranged within a space radially delimited by the stator of the second electric rotary machine.

[0025] According to a supplementary embodiment of the invention, the stators of the two electric rotary machines are arranged on a common stator carrier.

[0026] The stator carrier, in turn, is fixed to a housing of the drive unit. In particular, this stator carrier can be arranged radially between the stators of the two electric rotating machines and be mechanically connected to them, so that the stator carrier fixes both stators.

[0027] According to an alternative embodiment, the stators of the two electric rotary machines are integral components of a stator unit.

[0028] This stator unit can, in turn, be fixed to a housing of the drive unit. This alternative design therefore does not use an additional stator support between the individual stators, but rather comprises a compact unit formed solely by the two stators.

[0029] The stator unit can be secured to a drive unit housing using multiple screw connections. Each screw of a screw connection extends axially through the stator unit and is screwed into a drive unit housing.

[0030] In one embodiment of the drive unit, it comprises a first housing and a second housing, which together define a housing interior in which the two electric rotary machines are arranged and in which the first shaft and the second shaft are arranged at least in regions.

[0031] In particular, a common stator carrier or a stator unit is mechanically connected to the first housing, wherein the rotors of the two electric rotary machines are mounted on the second housing.

[0032] In particular, the second shaft can be mounted on the second housing, wherein the first shaft can be mounted on the first housing and on the second shaft.

[0033] In addition, power electronics for controlling the electric rotary machines can be carried by the second housing.

[0034] According to the invention, the two shafts are arranged coaxially. For this purpose, the second shaft is designed as a hollow shaft, and the first shaft extends partially within the second shaft.

[0035] According to a further embodiment, the drive unit comprises a first gear ratio, wherein the first gear ratio is formed by a connecting element of the drive unit, which comprises an internally toothed gear, and the first shaft, which has an element with external teeth, wherein the teeth of the internally toothed gear and the external teeth mesh with one another for the purpose of transmitting the rotary movement from the connecting element to the first shaft.

[0036] Accordingly, the drive unit according to the invention is designed as a so-called hybrid transmission. This means that, in addition to the electric rotating machines and the shafts, the drive unit also comprises a transmission. In particular, the element with the external toothing can be a gearwheel arranged in a rotationally fixed manner on the first shaft.

[0037] According to the invention, the drive unit has a second gear ratio stage which is formed by a toothing, in particular an external toothing, of the second shaft and a first gear meshing with the toothing of the second shaft.

[0038] In one embodiment in which the drive unit has a transmission, the first gear can be coupled in a rotationally fixed manner to an intermediate shaft of the transmission. This transmission can comprise a differential gear in the output range. In this case, an external toothing of the intermediate shaft can mesh with an input gear of the differential gear, thereby creating a third gear ratio. The second shaft thus functions as the transmission input shaft and is operatively connected to the transmission so that a torque provided by the second shaft or the rotary movement realized by the second shaft can be transmitted via the transmission in a stepped-up or stepped-down manner to another transmission unit of a motor vehicle, or can also be transmitted directly to the drive wheels of a motor vehicle.

[0039] The drive unit according to the invention has the advantage that, due to the axial nesting of the electric rotary machines, significantly less installation space is required axially than in conventional drive units with two electric rotary machines.

[0040] Furthermore, according to the invention, a drive arrangement is provided which has a drive unit according to the invention and an internal combustion engine, wherein an output element of the internal combustion engine is or can be coupled in a rotationally fixed manner to the rotor of the first electric rotary machine.

[0041] During operation of a motor vehicle, in particular a hybrid vehicle, with a drive arrangement according to the invention, comprising a drive unit according to the invention and an internal combustion engine, the following driving modes are possible, for example: Electric driving and recuperation: The separating clutch is open, decouples the second electric rotating machine from the first electric rotating machine and the internal combustion engine. The second electric rotating machine is thus controlled separately as a traction machine or as a generator. The internal combustion engine and the first electric rotating machine are not in operation. Serial driving and charging: The separating clutch is open. The internal combustion engine is started by means of the first electric rotating machine, whereby the internal combustion engine can drive the first electric rotating machine and consequently the first electric rotating machine is controlled as a generator to charge the motor vehicle's battery. The second electric rotating machine is controlled as a traction machine.Parallel hybrid drive, charging and boosting: The separating clutch is closed, coupling the first electric rotating machine, the second electric rotating machine, and the internal combustion engine. The motor vehicle is powered by the internal combustion engine and / or one or both electric rotating machines. The two electric rotating machines can be controlled as traction machines or generators. In a further embodiment, the drive arrangement also comprises at least one wheel drive shaft, on which wheels of a motor vehicle equipped with the drive arrangement are to be arranged, and which is connected to the second shaft of the drive unit via the transmission of the drive unit, so that a rotational movement realized by the second shaft can be transmitted through the transmission to the wheel drive shaft and thus to the wheels.

[0042] According to one embodiment of the drive arrangement, the drive arrangement comprises a vibration damper connected in a rotationally fixed manner to the connecting element of the drive unit and a housing element mechanically connected to the internal combustion engine, wherein the vibration damper is arranged in the housing element.

[0043] The housing element is advantageously connected to the second housing of the drive unit.

[0044] A pump actuator of a cooling circuit of the drive unit can be mounted in the housing element.

[0045] Furthermore, it can be provided that the intermediate shaft and / or the wheel drive shaft are mounted axially on the one hand in the housing element and on the other hand in the second housing.

[0046] The invention described above will be explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, and it should be noted that the embodiments shown in the drawings are not limited to the dimensions shown. It is shown in Fig. 1: a schematic representation of a drive arrangement according to the invention with a drive unit according to the invention, Fig. 2: a section of the drive arrangement according to the invention in a sectional side view, Fig. 3: a section of the drive unit according to the invention in the area of ​​electrical rotary machines and Fig. 4: a section of a drive unit according to the invention in the area of ​​electrical rotary machines in an alternative embodiment.

[0047] In Fig. 1A schematic representation of a drive arrangement 100 according to the invention with a drive unit 1 according to the invention is shown. The drive unit 1 comprises a first electric rotary machine 10, a second electric rotary machine 20, a first shaft 40, and a second shaft 41.

[0048] Furthermore, the drive assembly 100 comprises an internal combustion engine 110 and a vibration damper 101, wherein an output element 111 of the internal combustion engine 110 is coupled to the vibration damper 101. The vibration damper 101 is also connected to a connecting element 4 of the drive assembly 1, which functions as an input side 2 of the drive assembly 1. The internal combustion engine 110 is thus coupled to the drive assembly 1 via the vibration damper 110.

[0049] The connecting element 4 is coupled to the first shaft 40 such that a first transmission stage 70 is formed between the connecting element 4 and the first shaft 40.

[0050] A rotor 11 of the first electric rotary machine 10 is rotationally fixed to the first shaft 40, and a rotor 21 of the second electric rotary machine 20 is rotationally fixed to the second shaft 41. The connection of the rotor 11 of the first electric rotary machine 10 to the first shaft 40 is realized such that the rotor 11 of the first electric rotary machine 10 is arranged directly on the first shaft 40. The rotor 21 of the second electric rotary machine 20, on the other hand, is supported by a rotor carrier 30, and the rotor carrier 30 is connected to the second shaft 41.

[0051] The first electric rotary machine 10 is arranged radially and, in some areas, axially within a space radially delimited by the second electric rotary machine 20. The first electric rotary machine 10 is designed as an internal rotor motor, and the second electric rotary machine 20 is designed as an external rotor motor, with a stator 12 of the first electric rotary machine 10 and a stator 22 of the second electric rotary machine 20 being mechanically fixed to one another.

[0052] A separating clutch 50 of the drive unit 1 is connected by its input side 51 to the first shaft 40 and by its output side 52 to the second shaft 41. The separating clutch 50 thus serves to transmit torque between the first shaft 40 and the second shaft 41. Accordingly, a torque transmission path between the rotor 11 of the first electric rotary machine 10 and the rotor 21 of the second electric rotary machine 20 can be opened or closed by means of the separating clutch 50.

[0053] The second shaft 41 is designed as a hollow shaft, and the first shaft 40 extends radially within the second shaft 41 in sections. The two shafts 40, 41 thus extend coaxially to one another, with the rotors 11, 21 of the two electric rotary machines 10, 20 also being arranged coaxially to one another and coaxially to the shafts 40, 41.

[0054] The second shaft 41 is connected to an intermediate shaft 81 via a second gear stage 71. The intermediate shaft 81 runs parallel to the second shaft 41.

[0055] The intermediate shaft 81 is connected via a third gear stage 72 to an input element of a differential gear 80 of the drive unit 1 for the purpose of transmitting torque. The differential gear 80 forms an output side 3 of the drive unit 1.

[0056] A wheel drive shaft 103, on which wheels of a motor vehicle equipped with the drive arrangement 100 are to be arranged, forms the output of the differential gear 80, so that a rotary movement realized by the second shaft 41 can be transmitted via the second gear stage 71 and the third gear stage 72 as well as via the differential gear 80 to the wheel drive shaft 103 and thus to the wheels.

[0057] A torque provided by the internal combustion engine 110 is transmitted via the vibration damper 101 and via the first gear stage 70 to the first shaft 40 of the drive unit 1. If the separating clutch 50 is disengaged, the torque of the internal combustion engine 110 is only directed to the rotor 11 of the first electric rotary machine 10. In this way, the first electric rotary machine 10 can be used in generator mode to charge a battery. If the separating clutch 50 is engaged, the torque provided by the internal combustion engine 110 is transmitted from the first shaft 40 to the second shaft 41. From the second shaft 41, the torque of the internal combustion engine 110 is directed via the second gear stage 71 to the intermediate shaft 81 and via the third gear stage 72 into the differential gear 80.Via the differential gear 80, the torque is transmitted by means of the wheel drive shaft 103 to the wheels of a motor vehicle equipped with the drive arrangement 100.

[0058] A torque provided by the rotor 11 of the first electric rotary machine 10 can be transmitted to the internal combustion engine 110 via the first gear stage 70 when the separating clutch 50 is open. When the separating clutch 50 is closed, it can be transmitted to the differential gear 80 and thus to the wheel drive shaft 103 via the second gear stage 71 and the third gear stage 72.

[0059] A torque provided by the rotor 21 of the second electric rotary machine 20 is transmitted independently of the engagement of the separating clutch 50 via the second gear stage 71 and the third gear stage 72 to the differential gear 80 and thus to the wheel drive shaft 103.

[0060] The drive assembly 100 can accordingly be operated in a variety of driving modes.

[0061] Fig. 2 shows a section of the drive arrangement 100 according to the invention in a sectional side view.

[0062] The Figure 2 is a more detailed presentation of some of the Figure 1 indicated components, whereby in Figure 2 the internal combustion engine is not shown and the output element 111 of the internal combustion engine coupled to the vibration damper 101 is only partially shown.

[0063] In Figure 2A first housing 60, a second housing 61, and a housing element 62 can be seen, which are connected to one another and form an overall housing of the drive arrangement 100 or the drive unit 1. The first and second housings 60, 61 serve to accommodate the two electrical rotary machines 10, 20, wherein the housing element 62 serves to couple the first housing 60 and the second housing 61 to a housing of the internal combustion engine (not shown). For this purpose, the first housing 60 is firmly connected to the second housing 61 in the axial direction, wherein the housing element 62 is firmly connected to the second housing 61 on the side of the second housing 61 axially opposite the first housing 60.

[0064] The first shaft 40 is mounted with its first axial end region 42 via a single-row support bearing 92 in the first housing 60 and with its second axial end region 43 via a needle bearing 91 radially inwardly on a second axial end region 45 of the second shaft 41.

[0065] The second shaft 41 is supported by its first axial end region 44 on the second housing 61 via a central bearing unit 90. This central bearing unit 90 comprises two coaxially arranged rolling bearings positioned axially close to one another.

[0066] Furthermore, a common stator support 32 supporting the stators 12, 22 of the electric rotary machines 10, 20 is fixedly connected to the first housing 60, so that the stators 12, 22 of the electric rotary machines 10, 20 are supported by the first housing 60. The rotor support 30 of the rotor 21 of the second electric rotary machine 20 is mounted on the second housing 61 by means of a rolling bearing of the central bearing unit 90. A transmitter element of a rotor position sensor 34 is also connected to the rotor support 30, with a detector element of the rotor position sensor 34 being connected to the second housing 61, so that an angular position and / or a rotational speed of the rotor 21 of the second electric rotary machine 20 or of the rotor support 30 can be detected by the rotor position sensor 34.

[0067] In addition, the intermediate shaft 81 and the wheel drive shaft 103 are each mounted in the second housing 61 on their axial side facing the electric rotary machines 10, 20, and on their opposite axial side in the housing element 62. The connecting element 4 of the drive unit 1 is mounted on the housing element 62 via a double-row bearing unit 93. This double-row bearing unit 93 comprises two coaxially arranged rolling bearings positioned axially close to one another. The vibration damper 101 is arranged in the housing element 62.

[0068] The central bearing unit 90 and the double-row bearing unit 93 are each shown in different possible designs to illustrate their possible configurations. The central bearing unit 90 is shown with tapered roller bearings and angular contact ball bearings, while the double-row bearing unit 93 is shown with tapered roller bearings. However, as mentioned for the central bearing unit 90, other bearings, such as angular contact ball bearings, can also be used here.

[0069] Furthermore, power electronics 102 are arranged radially outwardly on the first and second housings 60, 61, wherein the power electronics 102 is configured to control the electric rotary machines 10, 20. A heat exchanger 105 of a cooling circuit for cooling at least one of the electric rotary machines 10, 20 is also arranged on the second housing 61 between the second housing 61 and the power electronics 102. A pump actuator 104 of this cooling circuit is supported by the housing element 62.

[0070] Figure 2 also shows a detailed structure of the gear ratios 70, 71, 72. The first gear ratio 70 is designed such that the connecting element 4 comprises an internally toothed gear 5 which meshes with an external toothing 46 on the second axial end region 43 of the first shaft 40.

[0071] The second shaft 41 also has an external toothing 47 at its second axial end region 45, with which it engages with a first gear 82, wherein the first gear 82 is arranged in a rotationally fixed manner on the intermediate shaft 81, so that the second transmission stage 71 is formed between the second shaft 41 and the intermediate shaft 81.

[0072] An external toothing 84 of the intermediate shaft 81 engages with a second gear 83 as an input element of the differential gear 80, whereby the third gear stage 72 is formed between the intermediate shaft 81 and the differential gear 80.

[0073] The separating clutch 50 corresponds to a frictionally lockable multi-plate clutch, the input side 51 of which is formed by inner plates which are arranged axially next to the rotor 11 of the first electric rotary machine 10 on the first shaft 40, wherein outer plates of the separating clutch 50 are connected to the second shaft 41 as its output side 52.

[0074] Radially outside the central bearing unit 90, an actuating system 53 for actuating the separating clutch 50 is arranged on the second housing 61, wherein a pressure pot of the actuating system 53 extends axially through the rotor carrier 30 in order to transmit an actuating force provided by the actuating system 53 to the separating clutch 50 for the purpose of closing it.

[0075] Furthermore, a locking screw 35 is provided, which is screwed into the first axial end region 44 of the second shaft 41, so that a screw head of the locking screw 35 exerts an axially acting preload force on the rotor carrier 30 and the two rolling bearings of the central bearing unit 90, whereby the axial position of the rotor carrier 30 and the central bearing unit 90 with respect to the second shaft 41 is secured.

[0076] In Fig. 3 a section of a drive unit 1 according to the invention in the area of ​​the electric rotary machines 10, 20 is shown.

[0077] The section shows a drive unit 1, identical to the embodiment of the drive unit 1 from Figure 2 .

[0078] You can see in Figure 3that the common stator carrier 32 is connected to the first housing 60 by means of a carrier screw 33. For this purpose, the carrier screw 33 is guided axially through a radially extending section of the common stator carrier 32 and screwed in the axial direction in the first housing 60.

[0079] In addition, the stator 12 of the first electric rotary machine 10, which is carried on the radial inner side of the common stator carrier 32, is axially offset from the stator 22 of the second electric rotary machine 20, which is carried on the radial outer side of the common stator carrier 32.

[0080] Alternatively to drive unit 1 from Figure 3 shows Figure 4 a section of a drive unit 1 according to the invention in the area of ​​the electric rotary machines 10, 20 in an alternative embodiment. Unlike Figure 3is that the stators 12, 22 of the two electric rotary machines 10, 20 are integral components of a stator unit 31. This stator unit 31 is fixed to the first housing 60 by a support screw 33, which extends axially through the entire stator unit 31 and is screwed axially into the first housing 60. This alternative embodiment therefore does not use an extra stator support between the individual stators 12, 22, but rather comprises a compact unit formed solely by the two stators 12, 22.

[0081] The drive unit according to the invention and the drive arrangement ensure optimal operation in a cost-effective and space-saving manner. List of reference symbols

[0082] 1Drive unit 2Input side of the drive unit 3Output side of the drive unit 4Connecting element of the drive unit 5Internal toothed gear of the connecting element 10First electric rotary machine 11Rotor of the first electric rotary machine 12Stator of the first electric rotary machine 20Second electric rotary machine 21Rotor of the second electric rotary machine 22Stator of the second electric rotary machine 30Rotor carrier of the second electric rotating machine 31Stator unit 32Common stator carrier 33Carrier screw 34Rotor position sensor 35Securing screw 40First shaft 41Second shaft 42First axial end region of the first shaft 43Second axial end region of the first shaft 44First axial end region of the second shaft 45Second axial end region of the second shaft 46External toothing of the first shaft 47External toothing of the second shaft 50Disconnect clutch 51Input side of the disconnect clutch 52Output side of the disconnect clutch 53Actuating system 60first housing 61second housing 62housing element 70first gear ratio 71second gear ratio 72third gear ratio 80Differential gear 81Intermediate shaft 82First gear 83Second gear 84External gearing of the intermediate shaft 90central bearing unit 91needle bearing 92support bearing 93double-row bearing unit 100Drive assembly 101Vibration damper 102Power electronics 103Wheel drive shaft 104Pump actuator 105Heat exchanger 110Internal combustion engine 111Output element of the internal combustion engine

Claims

1. A drive unit (1) for a drive train of an electrically driven motor vehicle, in particular a hybrid motor vehicle, having a first electric rotary machine (10) and a second electric rotary machine (20) and a first shaft (40) and a second shaft (41), wherein a rotor (11) of the first electric rotary machine (10) is connected in a rotationally fixed manner to the first shaft (40) and a rotor (21) of the second electric rotary machine (20) is connected in a rotationally fixed manner to the second shaft (41), and wherein the drive unit (1) further comprises a separating clutch (50) with which the rotor (11) of the first electric rotary machine (10) can be or is connected to the second shaft (41) for torque transmission, wherein one of the two electric rotary machines (10, 20) is arranged, at least in regions, radially and axially within a space radially delimited by the other electric rotary machine (10, 20), the separating clutch (50) is connected with its input side (51) to the first shaft (40), and with its output side (52), to the second shaft (41), the drive unit (1) has a second transmission stage (71) which is formed by a toothing of the second shaft (41) and a first gear (82) which meshes with the toothing of the second shaft (41), a torque provided by the rotor (11) of the first electric rotary machine (10) is transmitted via the second transmission stage (71) when the separating clutch (50) is closed, and wherein the two shafts (40, 41) are arranged coaxially, the second shaft (41) is designed as a hollow shaft and the first shaft (40) runs in sections within the second shaft (41), characterized in that the separating clutch (50) is designed as a multi-plate clutch, the input side (51) of which is formed by inner plates, which are arranged axially next to the rotor (11) of the first electric rotary machine (10) on the first shaft (40), and outer plates of the separating clutch (50) are connected to the second shaft (41) as its output side (52).

2. The drive unit (1) according to claim 1, characterized in that the first electric rotary machine (10) is arranged, at least in regions, radially and axially within a space radially delimited by the second electric rotary machine (20).

3. The drive unit (1) according to claim 2, characterized in that the first electric rotary machine (10) is designed as an internal rotor motor and the second electric rotary machine (20) is designed as an external rotor motor, wherein the stator (12) of the first electric rotary machine (10) and the stator (22) of the second electric rotary machine (20) are mechanically fixed to one another.

4. The drive unit (1) according to claim 3, characterized in that the stators (12, 22) of the two electric rotary machines (10, 20) are arranged on a common stator carrier (32).

5. The drive unit (1) according to claim 3, characterized in that the stators (12, 22) of the two electric rotary machines (10, 20) are integral components of a stator unit (31).

6. The drive unit (1) according to any one of the preceding claims, characterized in that the drive unit (1) comprises a first transmission stage (70), wherein the first transmission stage (70) is formed by a connecting element (4) of the drive unit (1), which comprises an internally-toothed gear (5), and the first shaft (40), which has an element with external teeth (46), wherein the teeth of the internally-toothed gear (5) and the external teeth (46) mesh with one another for the purpose of transmitting the rotary movement from the connecting element (4) to the first shaft (40).

7. A drive assembly (100) having a drive unit (1) according to one of claims 1 to 6 and having an internal combustion engine (110), which is or can be coupled in a rotationally fixed manner to the rotor (11) of the first electric rotary machine (10) via a drive element (111) of the internal combustion engine (110).

8. The drive assembly (100) according to claim 7, characterized in that the drive assembly (100) comprises a vibration damper (101) connected in a rotationally fixed manner to the connection element (4) of the drive unit (1) and a housing element (62) mechanically connected to the internal combustion engine (110), wherein the vibration damper (101) is arranged in the housing element (62).